Introduction
Fertility is, with mortality, one of the two big, overarching topics in demography. On a global scale population size and structure is entirely dependent on these two processes – fertility bringing people into the population and mortality taking them out.
At a sub-global level migration becomes an important third process which grows in importance as one considers smaller and smaller geographies.
So understanding fertility and the accurate estimation of it is extremely important and because of this it is approached in a variety of different ways, each with advantages and disadvantages for estimation procedures.
It is also an area where sociological explanations flood into the more precise measures that demography offers. There is a huge literature on reasons why women and couples decide to have more or less children and how governments have sometimes attempted to influence those decisions.
This is a fascinating area of demography but this session is concerned with the measurement of fertility rather than sociological theory.